URGENT!! Chemistry gurus-- I summon thee! 1. A solution is formed by dissolving 83.2 grams of copper II chloride (CuCl2) in 2.5 liters of water. The molar mass of CuCl2 is 134.45 g/mol.

What is the molarity of the solution?

I think its .25 but im not too sure

2. Study the reaction.

2CH4 + 2O2 → CO2 + 2H2O

If 7.4 moles of carbon dioxide (CO2) form at the end of the reaction, how many moles of methane (CH4) and oxygen gas (O2) entered the reaction?

answering both of these questions would be awesome but one is enough :)

1. Molarity : 0.25 M

2. mol CH₄ = 7.4 moles

mol O₂ = 14.8 moles

1.

Given

83.2 g CuCl2 in 2.5 liters of water

Required

the molarity

Solution

Molarity : mol solute per liter of solution(not per liter of solvent)

mol solute = mol CuCl₂

mol CuCl₂ = mass : MW CuCl₂

mol CuCl₂ = 83.2 : 134.45

mol CuCl₂ = 0.619

Molarity(M) = mol : V

Assume density CuCl₂ = 3.39 g/cm³

volume CuCl₂ = 8.32 g : 3.39 g/cm³ = 2.45 cm³=2.45 x 10⁻³ L

With this small volume value of CuCl₂, the volume of the solute is sometimes neglected in calculating molarity

volume of solution = 2.5 L + 2.45 x 10⁻³ L = 2.50245 L

Molarity(M) = mol : V

M = 0.619 : 2.50245 L = 0.247≈0.25

2.

Given

Reaction

The correct balanced reaction:

CH4 + 2O2 → CO2 + 2H2O

7.4 moles CO2

Required

moles of methane (CH4) and oxygen gas (O2)

Solution

From the equation, mol ratio of CO₂ : CH₄ : O₂ = 1 : 1 : 2

mol CH₄ = mol CO₂ = 7.4 moles

mol O₂ = 2 x mol CO₂ = 2 x 7.4 moles = 14.8 moles

first let us lay out the formula for potential

and kinetic energy:

pe = mgh

ke = (mv^2)/2

where: m=mass, v=velocity, g=gravitational

acceleration, h=height

calculating for mass using the known values of

pe:

340j = m (9.81 m/s^2) (50ft) (1m/3.28ft)

m = 2.27 kg

the law of conservation of energy states that

energy is neither created nor destroyed. therefore, the change in kinetic

energy from 50 ft to 35 ft would be equal to the change in potential energy

from 50 ft to 35 ft. however it would be opposite in signs since one is losing

while other is gaining.

ke(35ft) – ke(50ft) = - [ pe(35ft) – pe(50ft]

ke(50ft) = 0 since the brick is initially at rest

ke(35ft) = 340j - 2.27kg (9.81 m/s^2) (35ft)

(1m/3.28 ft)

ke(35ft)

= 102.38 j

b. th3 n4zc4 pl4t3 15 c0nv3rg1ng w1th the s0uth 4m3ric4n pl4t3.